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This module contains the Metro runtime code.
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 1997-2015 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* http://glassfish.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
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* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
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* exception as provided by Oracle in the GPL Version 2 section of the License
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*
* Modifications:
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package org.jvnet.mimepull;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.util.logging.Level;
import java.util.logging.Logger;
class FactoryFinder {
private static ClassLoader cl = FactoryFinder.class.getClassLoader();
static Object find(String factoryId) throws ClassNotFoundException,
InstantiationException, IllegalAccessException {
String systemProp = System.getProperty(factoryId);
if (systemProp != null) {
return newInstance(systemProp);
}
String providerName = findJarServiceProviderName(factoryId);
if (providerName != null && providerName.trim().length() > 0) {
return newInstance(providerName);
}
return null;
}
static Object newInstance(String className) throws ClassNotFoundException,
InstantiationException, IllegalAccessException {
Class providerClass = cl.loadClass(className);
Object instance = providerClass.newInstance();
return instance;
}
private static String findJarServiceProviderName(String factoryId) {
String serviceId = "META-INF/services/" + factoryId;
InputStream is;
is = cl.getResourceAsStream(serviceId);
if (is == null) {
return null;
}
String factoryClassName;
BufferedReader rd = null;
try {
rd = new BufferedReader(new InputStreamReader(is, StandardCharsets.UTF_8));
try {
factoryClassName = rd.readLine();
} catch (IOException x) {
return null;
}
} finally {
if (rd != null) {
try {
rd.close();
} catch (IOException ex) {
Logger.getLogger(FactoryFinder.class.getName()).log(Level.INFO, null, ex);
}
}
}
return factoryClassName;
}
}